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Based on kernel version 3.15.4. Page generated on 2014-07-07 09:03 EST.

1	Kernel driver htu21
2	===================
3	
4	Supported chips:
5	  * Measurement Specialties HTU21D
6	    Prefix: 'htu21'
7	    Addresses scanned: none
8	    Datasheet: Publicly available at the Measurement Specialties website
9	    http://www.meas-spec.com/downloads/HTU21D.pdf
10	
11	
12	Author:
13	  William Markezana <william.markezana@meas-spec.com>
14	
15	Description
16	-----------
17	
18	The HTU21D is a humidity and temperature sensor in a DFN package of
19	only 3 x 3 mm footprint and 0.9 mm height.
20	
21	The devices communicate with the I2C protocol. All sensors are set to the
22	same I2C address 0x40, so an entry with I2C_BOARD_INFO("htu21", 0x40) can
23	be used in the board setup code.
24	
25	This driver does not auto-detect devices. You will have to instantiate the
26	devices explicitly. Please see Documentation/i2c/instantiating-devices
27	for details.
28	
29	sysfs-Interface
30	---------------
31	
32	temp1_input - temperature input
33	humidity1_input - humidity input
34	
35	Notes
36	-----
37	
38	The driver uses the default resolution settings of 12 bit for humidity and 14
39	bit for temperature, which results in typical measurement times of 11 ms for
40	humidity and 44 ms for temperature. To keep self heating below 0.1 degree
41	Celsius, the device should not be active for more than 10% of the time. For
42	this reason, the driver performs no more than two measurements per second and
43	reports cached information if polled more frequently.
44	
45	Different resolutions, the on-chip heater, using the CRC checksum and reading
46	the serial number are not supported yet.
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